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Physical activity is not only beneficial to physical health but also to cognitive functions. In particular, executive functions that are closely related to learning achievement can be improved by acute and recurring physical activity. We examined the effects of a single 30‐min physical education program in contrast to a 5‐min movement break on working memory, cognitive flexibility, and inhibition of attention and behavioral tendencies of eighty‐one 13‐ to 14‐year‐old students in grade 7 in Germany. Results indicate that the maintenance of on‐task attention in the face of distraction was improved by an aerobic endurance exercise‐based physical education program but not by a short aerobic movement break. This suggests that the duration of a school sports program is decisive for improving students' executive attention.

The cumulative damage calculation method generally applied in the automotive sector is the Palmgren-Miner-Hypothesis with its modification according to Haibach. In several design codes the theoretical Palmgren-Miner damage sum D th = 1.0 is still recommended as the allowable damage sum D al despite the fact that it renders unsafe calculated fatigue lives.Results obtained with modern high-strength cast iron alloys such as EN-GJS-500-7, SiboDur 700-10 and MADI (Machinable Austempered Ductile Iron) under a standard Gaussian spectrum for chassis applications and also under a fuller injection pump spectrum suggest the allowable damage sum D al = 0.3 for fatigue life estimations.

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